Multi-view display system

ABSTRACT

Embodiments of the invention are generally directed to a multi-view display system. An embodiment of an apparatus includes a display screen to display multiple views simultaneously, and a controller to control the views presented on the display screen. The apparatus is configurable by the controller to provide multiple view settings, the view settings including a first setting in which the apparatus provides a single view to each viewer of the display screen and a second setting in which the apparatus provides a first view to a first viewer of the display screen and a second view to a second viewer of the display screen. A first filtering element filters views presented to viewers of the display screen such that an intended view is displayed to one or more viewers.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/848,037, filed on Jul. 30, 2010, which application is incorporatedherein by reference in its entirety.

TECHNICAL FIELD

Embodiments of the invention generally relate to the field of electronicdevices and, more particularly, a multi-view display system.

BACKGROUND

Display systems may display images or views to users of the systems. Adisplay screen for a system may include a television screen, a computerscreen, a movie screen, and other similar displays. There are often manydifferent possible views or programs that are available for a displayscreen.

If more than one image is desired for users, in a conventional systemmultiple screens may be used in one installation, or a single screen mayprovide multiple images by dividing the screen, such as in the use ofpicture-in-picture (PIP) and side-by-side modes for a display screen.

However, the use of a divided display screen compromises the utility orexperience that is provided by each of the displayed views on suchscreen. If a single display screen is divided, providing a split screen,then each image by necessity is smaller than the full size of thedisplay screen. If instead a picture-in-picture (PIP) display isutilized on a display screen, a foreground PIP program will be muchsmaller than full-size, and will occlude a portion of a backgroundprogram.

In addition, whether a divided screen or multiple screens are used, eachof the views that are provided on the multiple or divided screens isvisible to all users in a location or venue, thus creating a visualdistraction for all users and limiting the potential usage of thedisplay screen or screens.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are illustrated by way of example, and notby way of limitation, in the figures of the accompanying drawings inwhich like reference numerals refer to similar elements.

FIG. 1 is an illustration of an embodiment of a multi-view displaysystem;

FIG. 2 is an illustration of an embodiment of a multi-view displayapparatus;

FIG. 3 is an illustration of an embodiment of a filtering element foruse in a multi-view display system;

FIG. 4 is a flowchart to illustrate an embodiment of a process forproviding multiple views on a display; and

FIG. 5 illustrates an embodiment of a process for forcing compatibledevices to a common format;

FIG. 6 is an illustration of an embodiment of a multi-view displayapparatus or system;

FIG. 7 illustrates an embodiment of generation and display of multipleimages; and

FIG. 8 is an illustration of an embodiment of an electronic device orsystem for providing multiple image views.

SUMMARY

Embodiments of the invention are generally directed to a multi-viewdisplay system.

In a first aspect of the invention, an embodiment of an apparatusincludes a display screen to display multiple views simultaneously, anda controller to control the views presented on the display screen. Theapparatus is configurable by the controller to provide multiple viewsettings, the view settings including a first setting in which theapparatus provides a single view to each viewer of the display screenand a second setting in which the apparatus provides a first view to afirst viewer of the display screen and a second view to a second viewerof the display screen. A first filtering element filters views presentedto viewers of the display screen such that an intended view is displayedto one or more viewers.

In a second aspect of the invention, an embodiment of a method includesprojecting multiple images on a first display screen, and providingimages on the first display screen to one or more viewers, whereinproviding the images includes a first setting for providing a singleimage to all viewers of the first display screen and a second settingfor providing a first image to a first viewer and a second image to asecond viewer, and wherein providing the images includes filtering theimages projected by the first display screen to separate the images forviewing.

DETAILED DESCRIPTION

Embodiments of the invention are generally directed to a multi-viewdisplay system.

In some embodiments, a method, apparatus, or system provides for amulti-view display, wherein a display may provide multiple images tousers. Existing viewing systems provide the same view to all users on adisplay screen. However, different users may wish to watch differentviews, which may include images that are related to each other or imagesthat are not related to each other. In some embodiments, a group ofusers may share a display, with each individual or group of individualsseeing different material on the display. As used here, a displayproviding multiple different views at the same time is referred to as a“multi-view display”.

In some embodiments, multiple inputs to a television or other displaysystem or device may be shown simultaneously for viewing to allow userswith multiple choices of views. The views may include any images,including streams of video data, that are available to the displaysystem. For example, a first person may wish to view a sporting event ona home television screen, while a second person views a movie on thesame television screen. In another example, parents may wish to view anews program on the television while children watch a DVD or otherrecorded program on the same television screen. In some embodiments,some or all of the multiple programs are provided simultaneously on amulti-view display.

In some embodiments, multiple programs for a multi-view display may bereceived on different channels, such as different television channels,or the programs might be received from different inputs to the displaysystem or device. For example, programs directed to a multi-view displaymay include a live broadcast from a cable set-top box, a movie from aDVD player or other video storage medium, a video game from a gameconsole, and a computer program.

In some embodiments, multiple views may include partial images that areonly viewed by certain users and not others. For example, a multi-viewdisplay may limit a PIP to only certain users, such as a circumstance inwhich everyone in a room may view a movie or other similar program,while only a subset of users see an inset of another program, such as alive football game. In another example, only a subset of viewers mayview certain added text, where the text might be related information,such as subtitles for a film that only certain viewers see, or might beunrelated information, such as sports scores that only certain viewerssee.

In some embodiments, a multi-view display apparatus or system includes aplurality of different view settings or states, including a firstsetting in which a single view is provided to all viewers of themulti-view display and a second setting in which a first view isprovided to a first viewer and a second view is provided to a secondviewer. In an example, a multi-view display apparatus or system maychoose between providing a single three-dimensional (3D) image to eachviewer of the display or providing different images to differentviewers, such as a first two-dimensional (2D) image to a first viewerand a second 2D image to a second viewer. However, embodiments are notlimited to these images, and may include various different displays of2D and 3D images.

In some embodiments, a multi-view display may operate by utilizing asingle video stream that provides multiple images in different regionsof an image. In an example, a gaming system may utilize a single videostream with different regions of the total image serving differentusers. In some embodiments, a control unit operates to extract thedifferent regions of the image, scale each region up to a full sizedimage, and present each image to the appropriate viewer or views. In anexample, a left side region of an image may be targeted to a firstviewer, while the right side region of the image is targeted to a secondviewer. In some embodiments, the control unit separates the two regions,scales each region to a full screen size, then provides the expanded,full screen size left view to the first viewer and the expanded, fullscreen right view to the second viewer.

FIG. 1 is an illustration of an embodiment of a multi-view displaysystem. In some embodiments, a multi-view display system 105 includes adisplay 110 to provide multiple views. As shown, the multiple viewsinclude a first view 115 resulting from a first stream of video data 125and a second view 120 resulting from a second stream of video data 130,where the streams of video data are shown being provided by a controlunit 135 of the multi-view display system 105. While FIG. 1 illustratestwo views being presented by the multi-view display system 105,embodiments are not limited to this number of views, and may provide twoor more views. While for ease of explanation this discussion generallydescribes views that include a single set of data for an image, thus atwo-dimensional (2D) representation, embodiments may also includethree-dimensional (3D) images that may require multiple sets of data foran image, such as a first stream of data for a left eye image and asecond stream of data for a right eye image.

In some embodiments, in a first setting, a single view may be providedto all viewers of the display 110 and in a second setting, a first viewmay be provided to one or more viewers of the display 110 while a secondview is provided to one or more other viewers of the display 110. Inthis illustration, the multiple views 115 and 120 are presented tomultiple different users or users, shown here as a first user 150, asecond user 155, and a third user 160. In some embodiments, multipleusers or groups of users may observe the different views presented onthe display 110. In some embodiments, each user is able to choose or tobe assigned one of the multiple views. In some embodiments, a certainintended view of the multiple views is allowed through a filteringdevice or element for viewing by a user, with other views being filteredout such that these other views are not seen by the user.

In this illustration, first filtering device or element 165 allows firstview 115 to be viewed by first user 150, while filtering out second view120. Further, second filtering device or element 170 and third filteringdevice or element 175 allow second view 120 to be viewed by second user155 and third user 160 respectively, while filtering out first view 115.For the purposes of this illustration, a single filtering device orelement is provided for each user, but embodiments are not limited tothis implementation. In some embodiments, a single filtering device orelement may be used for some or all of a group of users, and in someembodiments, multiple filtering devices or elements may be used for eachuser.

FIG. 2 is an illustration of an embodiment of a multi-view displayapparatus. In some embodiments, a multi-view display apparatus 200includes a control unit 205, and includes or is coupled with a display210. In some embodiments, the display 210 displays multiple viewssimultaneously, such as first view 215 and second view 220 through annth view 225. In some embodiments, the control unit 205 includes acontroller 235 to control the presentation of the multiple views on thedisplay 210, including the implementation of at least a first setting toprovide a single view to all viewers of the display and a second settingto provide different views to different viewers of the display. In someembodiments, the control unit 205 provides multiple video streams 230via a link, such as provided via an output port 240, to generate thevarious views 215-225. In some embodiments, the link utilized totransmit multiple video streams may also transmit corresponding audiostreams.

In some embodiments, the control unit 205 includes a memory 245 to holdor buffer data for presentation of the multiple views. In someembodiments, the control unit 205 includes a transmitter 250 to transmitsignals to filter elements, such as signals to direct the switching ofswitching filter elements, and a receiver 255 to receive signals fromfilter elements, such as status signals received from filter elements ordevices including filter elements, via one or more antennas 275 or othercommunication elements. In some embodiments, the control unit 205includes an input port 260 to receive one or more data streams forpresentation on the display 210. In some embodiments, the control unit205 includes a position element 265 to determine or detect the positionof one or more users in relation to the display 210. In someembodiments, the control unit includes an alignment element 270 to alignmultiple video streams with each other for display.

In some embodiments, control unit 205 may be utilized for video gameoperation. In some embodiments, a computer or console game system mayinclude a multi-view display for multi-player game play. In animplementation, a display screen may project a video game in whichmultiple players use the same display, but with each player seeingdifferent views. A conventional gaming system may include a split-screenview, but such a split-view results in effectively reducing a screensize for each user. Furthermore, in the conventional system, each playercan see the other's view, which may be an impediment or disadvantage forcertain games. In an example of a first person shooting game or similargame, the ability of a first player to act without knowledge of a secondplayer, such as to sneak up on the second player, may be an importantpart of the game play. The ability to accomplish this is significantlycompromised if each player can see the other player or players' screens.In some embodiments, a multi-view display provides each player (or groupof players) with a distinct, full-sized image that is not visible toother players, thereby allowing full screen viewing with individualviews for each player or group of players.

In some embodiments, multiple views are initially combined in a singleimage, wherein certain regions of the image are intended for differentviewers or groups of viewers. In some embodiments, the control unit 205operates to separate the regions of the image, scale each region up to alarger (such as full screen) size, and present the multiple images toviewers. In this manner, a device or system that is generating imagesfor multiple viewers is only required to provide a single data stream,rather than multiple data streams. In an example, a gaming system thatprovides side-by-side image regions for two players may provide theimage stream to a multi-view display apparatus or system, and themulti-view display apparatus or system may operate to extract the imagesfor simultaneous full-screen display to players of the game.

In some embodiments, a multi-view display system or device is utilizedto provide a head-tracked view to multiple people simultaneously.Stereoscopic displays are a popular technology for giving users theillusion of depth in conventional systems. However, stereopsis is notthe sole depth-cueing mechanism for human vision, with motion parallaxbeing another depth cue for a viewer. Motion parallax is the phenomenonproviding that, as the viewpoint changes, close objects appear to move agreater amount than far objects. In some embodiments, a computergraphics system may provide a depth cue by observing or detecting theposition of the system user relative to the display, and rendering ascene that is rendered as a view from the user's position. Adisadvantage of conventional head-tracking systems is that displays canonly show a scene rendered from a single viewpoint, and thus eachdisplay can only provide head tracking for a single user. For thisreason, multiple user systems have required the use of multipledisplays, such as, for example, a pair of VR (Virtual Reality) gogglesto provide the required display for each user. In some embodiments, amulti-view display device or system may be used to remove thislimitation in head-tracking displays, the display providing a differenthead-tracked view for each user.

In some embodiments, a multi-view display device or system may includeone or more stereoscopic image streams. In some embodiments, amulti-view display with three or more independent channels may show botha stereoscopic (three-dimensional, or “3D”) stream and a non-stereo(two-dimensional, or “2D”) stream. In some embodiments, a multi-viewdisplay with four or more independent channels may show multipleindependent stereoscopic streams. In some embodiments, a display mayutilize multiple stereo streams to display multiple head-tracked,stereoscopic streams, thereby potentially providing each user with anindependent view having multiple depth cues (stereopsis and motionparallax.)

In some embodiments, a multi-view display may be used to customizecontent for different groups of users. In a particular example,different advertisements may be directed to different users of amulti-view display system or device, with, for example, the choice ofadvertisements being related to a choice of view made by each viewer.

In some embodiments, a system may utilize and combine different elementsfor multi-view systems. For example, a system may provide a combinationof directed content and PIP views directed to individuals who havechosen certain video streams on a multi-view display system.

In some embodiments, certain venues that are well suited for providingmultiple views to users may include multi-view displays. For example, amovie theater utilizing a multi-view display may project multiple moviesin a single room. It is common that, as movies near the end of theirtheater run, theaters showing such films are nearly empty. The abilityto show multiple movies on a single screen would allow theater complexesto offer more programs or start time selections for a given number oftheater screens. In some implementations, movies may be chosen togetheror combined for certain effect or attraction to audiences. For example,specific combinations of programming (a romantic movie shown at the sametime as an action movie) may be used to attract couples or other groups.In some embodiments, the number of persons viewing each movie may bedetermined by determining how many filter element glasses are set foreach view.

In some embodiments, a venue that currently has a shared display, suchas an airplane with a shared display (often a ceiling-mounted display)may expand to provide passengers or other users a choice of programs. Inthe example of video delivery to an airplane screen, the venueconventionally has a provision for delivery of independent audio streamsthat passengers may listen to via headset to provide audio for each ofthe chosen video streams.

Stereoscopic displays have become increasingly popular. Such systemsgenerally utilize a mechanism to display two related images, such thatone of the related images is provided to a user's left eye and a secondis provided to the user's right eye, thereby creating an impression ofimage depth to the user. In such an application, the two images areclosely related, with each providing a view of the same scene from aslightly different perspective. Moreover, each user receives the sametwo images.

In some embodiments, a filtering element, such as a pair of glasses, maybe used by a user to view a particular display or view provided by amulti-view display system. In this description, “glasses” refer to anyoptical device utilized by a user of a multi-view display system, andmay include a pair of eyeglasses, a set of goggles, or other similardevice.

FIG. 3 is an illustration of an embodiment of a filtering element foruse in a multi-view display system. In some embodiments, the filteringelement may be in the form of separate filters provided for each user,such as glasses 305 or similar element to be worn by individuals. Insome embodiments, the filtering element may be a part of or anattachment to a multi-view display 350, such as a lens or filter 355 forthe multi-view display 350. In an example, the lens or filter may be adirectional lens or filter that allows a different view in differentlocations.

In some embodiments, the glasses include a separate filter for each eye,such as left eye filter (the filter for the left eye of a user) 315 andright eye filter 310. The filters may include, but are not limited to,the filters described herein, such as polarized filters, shutters, andcolor filters. In some embodiments, the filters 310-315 may be fixedelements, for which a view for a user is selected by choosing a set ofglasses that are compatible with the selected view.

In some embodiments, the filters 310-315 are selectable filters, andthus the glasses 305 may be set for the selected view. In someembodiments, the glasses 305 may include a switching element 330 forswitching the filters to the appropriate settings for the selected viewsetting. In some embodiments, the switching element 330 may be set bythe user, and in some embodiments, the switching element 330 may beremotely switchable, such as in response to a signal from the multi-viewswitching system. In some embodiments, the glasses may include atransmitter, receiver, or both, shown as transceiver 320, to sendsignals to the system, receive signals from the system, or both.

In some embodiments, the glasses 305 may include one or more sensors 335to detect a state of the filter element, the state including, forexample, whether the glasses are in use, the view to which the glassesare set, the location of the glasses in relation to the multi-viewdisplay system, and other data regarding the use of the glasses. Thesensors 335 may further include a sensor to determine a direction of theglasses 305, such as would be used in a head tracking implementation.

Many display technologies for multi-view displays may require that eachuser of the display wear a pair of glasses to filter out unwanted videodata. In some embodiments, because each user is wearing glasses, otherfunctions are combined with the filtering function in the glasses. Insome embodiments, the glasses 305 may include a sound element 325, wherethe sound element provides an audio stream that relates to a videostream for the selected view. For example, the glasses 305 may includeearphones to present the appropriate audio to user. In some embodiments,the audio stream may be received from the multi-view display system,such as through the transceiver 320.

In some embodiments, glasses used for multi-view displays further allowa user to select which video stream to view. In some embodiments, activeglasses, such as shutter glasses based on LCD lenses, may include abutton, switch, or dial that selects which view of multiple displayedviews the user wishes to receive. In some embodiments, passive glassesbased on polarizers may include mechanical selection of views. Forexample, polarized glasses that allow a ninety-degree rotation of theirlenses could be used to select views. Circular polarizers are typicallyconstructed of a linear polarizer and a quarter-wave plate. If theglasses permit a ninety-degree rotation of one against the other, thehandedness of the lenses can be controlled mechanically. This may beaccomplished with rotation of the quarter-wave plate while the polarizerremains fixed, rotation of the polarizer while the quarter-wave plateremains fixed, or differing rotation of the two.

In another example, a pair of glasses may consist of quarter-wave plate,linear polarizer, and quarter-wave plate. With the appropriate alignmentof the three layers, reorienting the lenses may change between left- andright-handed polarization, and thus may be used to select a view.

In some embodiments, a liquid-crystal polarizer may be substituted for alinear polarizer, with electronic control of the orientation of theliquid crystal substituting for physical rotation of the polarizer. Insome embodiments, the glasses may include a control for the user toselect which view the glasses deliver. Embodiments in which each eye maybe controlled independently may be used for both multi-view andstereoscopic viewing.

In some embodiments, controllable glasses may be controlled by amulti-view display system rather than directly by a user. In such asystem, numerous pairs of glasses may be controlled. In someembodiments, a system utilizes a communication channel, such as infraredor Bluetooth channel, over which glasses could be addressed,individually or in groups, to provide a signal to direct which view eachpair of glasses or group of glasses should see. In some embodiments, apair of glasses includes or has access to a receiver, such as a portionof transceiver 320 of FIG. 3, to receive the signal, and is operable toswitch to a chosen channel in response to a received signal. In someembodiments, a system may utilize glasses in, for example, a group gamewith changing teams. In an example, a two-view display may pick the bestsuited of multiple possible advertisements for each user in a largegroup. A display could direct the glasses worn by users to switchbetween multi-view and stereoscopic modes as appropriate to the contentit is showing.

In some embodiments, an additional function that glasses may perform isto deliver appropriate audio to a user. A user wearing glasses to view aparticular video stream may also require separate audio, and thus it maybe useful to combine audio delivery with video delivery. In someembodiments, a pair of glasses would receive audio from a multi-viewdisplay or system over a wired or wireless communication channel (e.g.Bluetooth, or other radio frequency (RF) channel). In some embodiments,glasses may include a set of headphones or similar device, such aselement 325 of FIG. 3. In some embodiments, the glasses may eitherreceive all audio programs from the display and present only one to theuser, or include a back-channel used to select the audio program sent bythe display. Glasses with a mechanism for the user to select the videoprogram, as described above, would automatically select thecorresponding audio program.

In some embodiments, an additional function for glasses used in amulti-view display system is to sense when the glasses are in use and tocommunicate this information to the display system. In some embodiments,glasses may include sensors such as sensors 335 of FIG. 3. In someembodiments, the glasses may sense when the glasses are in use with: aswitch the user operates (such as a power switch); a contact sensordetecting when the glasses are on a user's head; a light sensor that isoccluded when the glasses are on a user's head; or a switch that detectswhen the temples of the glasses are unfolded. In some embodiments,glasses may communicate their status as being in use to the displaysystem over a wireless link, such as Bluetooth, infrared, RF, or Wi-Fi,as illustrated by transceiver 320 of glasses 305 in FIG. 3. In someembodiments, glasses, whether fixed glasses or switchable glasses, maycommunicate the view to which the glasses correspond. In an example, ifa particular set of glasses may be switched between a first view and asecond view, and such glasses are in use in the first view, the glassesmay provide a signal to the multi-view display system indicating thatthe glasses are in use and are set to the first view.

In some embodiments, a multi-view display system may sense which glassesare in use based on signals received from viewing glasses, and thuswhich streams are requested, and the system may use this information tooptimize the display. For example, a multi-view display based on shutterglasses may direct the glasses to remain consistently open when only onestream is needed, thus reverting to a single-view display.

In some embodiments, a system may optically sense which devices are inuse through use of a camera, where the camera generates a view of theusers and the system detects distinguishing marks, such as distinguishedpatterns, on the glasses.

In some embodiments, users viewing independent streams via a multi-viewdisplay system may be provided a means of controlling the scenesindependently. In some embodiments, a multi-view display system providemultiple remote controls, or other user interface devices, and provide ameans for identifying which view the remote is controlling. In animplementation of a system where view selection is accomplished withglasses, each of pair of glasses and corresponding remote control may beprovided with a common marking: for example red-framed glasses and a redremote for view 1, and blue-framed glasses and a blue remote for view 2.

In some embodiments, a multi-view display system for a multi-viewdisplay may include:

(1) Display technologies may separate the images for left and right eyesby presenting them with different polarization, such as by usingleft-handed polarization for one eye and right-handed for the other. Forstereoscopic viewing, a user may use a filtering element, such as a pairof glasses, in which each eye has a different circular polarizer. Insome embodiments, for viewing multiple independent streams with amulti-view display, at least two different varieties of glasses may beused, such as a pair of glasses with left-circular polarizers in eacheye to allow a first user to see only a first stream of images, and apair of glasses with right-circular polarizers in each eye to allow asecond user to see only a second stream of images. For example, forglasses 305 illustrated in FIG. 3, the left eye filter 315 and the righteye filter 310 may be matching. Certain display technologies similarlyutilize orthogonal linear polarizations, for example vertical andhorizontal polarization.

In an example, a system provides a stereoscopic image and anon-stereoscopic image on a multi-view display. In an example, a pair ofglasses with, for example, both eyes left-circular polarized may allow auser to see a non-stereoscopic view of a stereoscopic display. In animplementation, a user who finds stereo 3D content objectionable mayutilize these glasses to see a 2D view of the movie, while sharing atheater with friends who enjoy the 3D effects.

(2) In some embodiments, a line-alternate polarizing display may be usedfor a multi-screen display. In some embodiments, the number of verticallines may be increased to preserve the resolution of the display inindependent mode. In an example, the number of vertical lines may bedoubled to allow two users to view full resolution images, such as a1920×2160 display being utilized to display two independent images atfull 1080p resolution.

(3) In some embodiments, a time sequential display may be implemented ina multi-view display system or device. A stereoscopic display may usetime-sequential display of left and right images, wherein, for example,the left view is provided in even frames and the right view is in oddframes. In a stereoscopic system, matching active shutter glasses may beutilized to open view at the correct times for the left eye to view theeven frames and the right eye to view the odd frames. In someembodiments, a time sequential display is utilized to display twoindependent data streams. If, for example, a first data stream isprovided in even frames and a second data stream is provided in oddframes, then a first set of glasses (for viewing the images representedby the first data stream) would open both eyes to view the even framesand close both eyes to avoid viewing the odd frames, while a second setof glasses (for viewing the images represented by the second datastream) would open both eyes to view the odd frames and close both eyesto avoid viewing the even frames.

While the above example illustrates an implementation utilizing two datastreams, embodiments using time-sequential display are not limited totwo data streams. In some embodiments, three or more independent imagesmay be shown, with the number of independent images being limited onlyby factors such as the brightness, response time, bandwidth, and otherfeatures of the display.

(4) In some embodiments, a system may utilize multiple sets of primarycolors, such as six primary colors (two red, two green, two blue) withslightly varying wavelengths, with matching glasses to filterappropriately to show stereo contents. In some embodiments, varyingprimary colors are used to provide multiple independent images. In anexample, the same filter may be provided in each eye of any pair ofglasses, but with the filters differing depending on which data streamis to be viewed by the pair of glasses. In some embodiments, any numbern data streams, n≧2, may be viewed on a multi-view display screen byutilizing n different types of glasses, by using n reds, n greens, and nblues, if there is sufficient light produced by a light source and ifwavelength filters sufficiently differentiate between light frequencies.

In some embodiments, any of the preceding described implementations maybe combined to increase the number of independent images provided by amulti-view display system or device. For example, a circularly polarizedmethod (providing two channels) may be combined with analternating-frame time sequential method (providing two channels) toyield four independent channels.

In some embodiments, additional display techniques for stereo may beutilized to view multiple images on a multi-view display. In an example,lenticular displays provide different images at different viewing anglesof a display, which may be used in certain circumstances forstereoscopic images. In some embodiments, multiple views may be providedto different users depending on the viewing angle for the user. Suchdisplay technology may be used in, for example, the front of anautomobile to show a movie to a front-seat passenger while occludingview by the driver in order to avoid distraction, or to show anavigation display to the driver while the passenger sees anentertainment program. In some embodiments, lenticular displays may becombined with other approaches to increase channels for viewing. Forexample, a display that is both lenticular and polarized could offer twochannels to the left side of a room or other location, and twoadditional channels to the right side of the room.

In some embodiments, anaglyph and other complementary-color filters(red/cyan, amber/blue, magenta/green, etc.) may be used for stereodisplay. In some embodiments, such filters may be combined with anothertechnology for providing multiple viewing to provide multiplestereoscopic images from a multi-screen display.

In some embodiments, a system or device may transport, combine, andprocess video data so that such video data may be displayed on amulti-view display. In some embodiments, a multi-view display includesinputs to allow input of multiple streams simultaneously. In someembodiments, a system may utilize multiple existing video inputs.

In some embodiments, a method or process for conveying multiple streamson a single link is provided. A single device may be the source ofmultiple streams, as in the case of a game console generating views formultiple players. In some embodiments, video switching equipment such asaudio/video receivers could be multi-stream aware. Such a link couldalso be used between devices inside a multi-view display.

Varying approaches may be utilized for conveying stereoscopic video overlinks, and in some embodiments such formats are reused and extended toprovide for viewing of multiple images by different users. In a specificexample, the HDMI™ (High-Definition Multimedia Interface) standarddefines formats for 3D content. In some embodiments, the formats may beused to transport two independent streams of identical video format. Inthis example, metadata may be used to indicate that the two data streamsare independent, as opposed to the data streams being parts of a 3Dpresentation. In an example, the metadata might take the form ofcurrently reserved values in the 3D Structure field of the HDMI VendorSpecific Info Frame. In another example, metadata may also use acurrently reserved bit elsewhere in the HDMI Vendor Specific Info Frame,or use a newly defined vendor-specific Info Frame.

In some embodiments, existing formats and techniques for transportingstereoscopic video can be generalized to allow more than two streams tobe carried. For example:

(1) Three or more side-by-side images at full resolution;

(2) Three or more side-by-side images at reduced horizontal resolution(including such that the combined images fit into the native resolutionof the display);

(3) Three or more horizontally-, vertically-, or diagonally-interlacedimages; or

(4) Three or more frame-interleaved streams.

In the transport of stereoscopic video, it is generally assumed that thevideo or images for the left and right eyes are of the same format. Whenmultiple independent streams are transmitted, it is possible that theformat of the streams will differ. In some embodiments, for streams withthe same frame rate but different resolution, the largest format may beutilized, with metadata added to each video stream indicating the sizeof each stream. In some embodiments, a multi-view display may beutilized for combined streams that differ in size. In some embodiments,utilizing side-by-side formats, each image may be sent at its nativewidth but with padding at the bottom and/or top of the image, thusreducing a required dot clock while providing consistent horizontal andvertical sync signals. Conversely, in some embodiments utilizingframe-interleaved formats, each image may be sent at its native heightbut with padding at right and/or left, thereby reducing bandwidth whileproviding consistent sync signals.

In some embodiments, data for multi-view formats are presented to adisplay system or apparatus that is multi-view aware and handles themultiple views as separate views. In some embodiments, a link mayinstead carry multiple streams in such a manner that a non-multi-viewaware display would show such streams as a single stream. In someembodiments, the streams may be encoded in a frame-interleaved fashion,with all streams except the first contained within the vertical blankinginterval; or in a side-by-side fashion, with all except the firstcontained within the horizontal blanking interval. In some embodiments,presence of the multiple streams to the multi-view aware could beindicated with metadata, or the receiver could detect the alteredhorizontal or vertical sync timing automatically.

FIG. 4 is a flowchart to illustrate an embodiment of a process forproviding multiple views on a display. In some embodiments, multiplestreams of data are transmitted to provide multiple views for display405. In some embodiments, the multiple streams may be utilized in aplurality of different settings, such as a first setting in which asingle view is provided to all views and a second setting in whichdifferent views are provided to different viewers. In some embodiments,a system may be required to identify a first view to be provided for afirst user 410 if the view is to be set by the system. In someembodiments, a filtering element is provided to filter views such thatthe first view is provided to the first user and other views arefiltered out 415. The type of filtering element varies in differentembodiments. In some embodiments, filtering elements may be included inglasses worn by users. In some embodiments, a filtering element may beprovided in a display apparatus.

In some embodiments, if the filtering element is selectable 420, thefiltering element may be set to a first view 425. If the system includesremote access for switching to a view 430, such as when the glasses wornby a user are addressable by the multi-view display system, then asignal is sent to the filtering element and the filter is set inresponse to the signal 435. If the system does not include remote accessthen the user may be allowed to switch the filtering element 440, suchas setting switchable glasses to a particular view. If the filterelement is not selectable 420, then the appropriate filtering elementmay be provided or made available to the first user 442, such as, forexample, providing glasses that include proper lens and filters for aparticular view.

In some embodiments, if a filter element includes a sensor to determinea state of the filtering element, such as whether the glasses are inuse, what view the glasses are set to, or both, and a transmitter toreport data back to the multi-view display system 445, then a signal issent from the filter element to the multi-view display system regardingthe state of the filter element 450 and such signal may be received atthe multi-view display system 455. The selected first view is presentedto the first user 460, with the filtering element filtering other viewsfrom the display to prevent such views from reaching the first user.

In some embodiments, individual systems or devices may be sources,sinks, or both of multi-stream video data. In some embodiments, aparticular class of system or device accepts multiple independentstreams and combines the streams, either for transport or for directdisplay. In some embodiments, the system or device may interleave thestreams as appropriate for the display or transport format. In someembodiments, the system or device may select streams from a subset ofits inputs.

In some embodiments, before multiple video streams are combined fordisplay or transport, the video streams may be converted or adjusted toa common format, temporal relationship, or both. In some embodiments,similar requirements may be implemented in other video processingdevices or systems, such as, for example, in production equipment fortelevision broadcast.

In some embodiments, a device or element for video alignment (referredto herein as an aligning device) may accept streams in arbitrarilydifferent formats. In some embodiments, the aligning device performsimage scaling, frame-rate conversion, and interlacing or deinterlacingas needed to bring the input streams to a common format. In someembodiments, the aligning device may further buffer data as required sothat the data is available when needed for display or output.

In some embodiments, a system or device may operate to eliminate orreduce processing or buffering required to align video streams for amulti-view display. In some embodiments, an aligning device may forceall inputs to have a compatible format, such as requiring inputs to havethe same resolution, have the same frame rate, and either be interlacedor not interlaced, and by doing so eliminate the need to performscaling, frame-rate conversion, and interlacing/deinterlacingrespectively. In an example, a system or device may use hot-plugtechnology and EDID (Extended Display Identification Data) to force HDMIcompatible devices to a common format. FIG. 5 illustrates an embodimentof a process for forcing compatible devices to a common format. In anexample, a process provides:

1. Choose a primary input 505.

2. Observe the video format (primary input format) on the primary input510.

3. Generate or simulate an unplug event on all desired inputs other thanthe primary 515.

4. Present an EDID that advertises only the primary input format toinputs other than the primary input 520.

5. Generate or simulate a plug-in event on all desired inputs other thanthe primary 525.

6. Allow sources to send a defined default format 530. Should any sourcesend the default format when that is not the primary input format 535,the aligning device may, for example, refuse to process video from theinput in question or force all inputs, including the primary, to thedefault format 540, using a process similar to processes 3-5. Otherwise,the process continues with multi-display operation 545.

In some embodiments, a process may be enhanced to search for a bestformat common to a group of desired sources, where best may defined by apreference list or other metric. In some embodiments, a process may beenhanced with an aligning device that may perform one or more ofscaling, frame-rate conversion, or interlacing/deinterlacing.

In some embodiments, an aligning device may reduce buffer requirementsby forcing all inputs to have the same video timing. Mechanisms mayinclude gen-lock, line-lock, and frame-lock, depending on thegranularity and accuracy of synchronization required. For example, forpixel-interleaved formats, fully gen-locked sources require very littlebuffering.

In some embodiments, an aligning device may use a gen-lock-, line-lock-,or frame-lock-like mechanism, but with the mechanism used to forcedevices to a specific phase relationship other than in-phase. Forexample, a device that is combining two streams into a frame-interleavedformat may reduce buffering by forcing the half an input frame time outof phase. In an example, a system or device acting to combine three datastreams into a side-by-side format may reduce buffering by forcing thesecond inputs to be delayed by one-third and two-thirds of a line timerespectively.

FIG. 6 is an illustration of an embodiment of a multi-view displayapparatus or system. In this illustration, a multi-view displayapparatus or system 600, including, for example, multi-view displayapparatus 200 illustrated in FIG. 2, includes a plurality of settings605 for providing images to viewers.

In some embodiments, the settings 605 of the multi-view displayapparatus or system 600 may include a first setting to provide a same 3Dview to all viewers 610, illustrated as 3D view 615. In someembodiments, the settings 605 may include a second setting to provide asame 2D view to all viewers 620, illustrated as 2D view 625. In someembodiments, the settings may include a third setting in which differentviews are provided to different viewers 630. In some embodiments, theviews may include a mixture of 2D and 3D views, depending on the contentthat is available for viewers. In this illustration, the views mayinclude a first 3D view 635, a second 3D view 640, a first 2D view 645,and a second 2D view 650.

In some embodiments, the apparatus or system 600 may dynamically switchbetween settings 605 as required. In some embodiments, the apparatus orsystem 600 may instruct or set a filter or filters, such as filteringdevices or elements 165-175 illustrated in FIG. 1, to all be set to thesame setting to provide the 2D or 3D view. In some embodiments, the useof a single view may occur at a beginning, end, or other point in animage presentation when all viewers should view a single view. Forexample, the single view may be an introductory image for all viewers;an emergency image to communicate a message to all viewers; or otherimage intended for all viewers.

FIG. 7 illustrates an embodiment of generation and display of multipleimages. In this illustration, an input data stream 705 includes aplurality of images in different regions of the data stream. As shown inFIG. 7, the input data stream may provide a first image in a firstregion 710, shown here as a left half region, and a second image in asecond region 715, shown here as a right half region. FIG. 7 illustratestwo regions for simplicity, but embodiments are not limited to anyparticular number of regions.

In some embodiments, the images contained in the regions are scaled upsuch that such images are larger (such as full-screen) images. In thisillustration, the first image 710 is scaled up to generate a firstfull-screen image 720 and the second image 715 is scaled up to generatea second full-screen image 725.

In some embodiments, the enlarged/full-screen images are presentedsimultaneously to viewers, illustrated here as first full-screen image735 and second full-screen image 740 being displayed together on amulti-view display screen 730.

FIG. 8 is an illustration of an embodiment of an electronic device orsystem for providing multiple image views. In this illustration, certainstandard and well-known components that are not germane to the presentdescription are not shown. Under some embodiments, a device or system800 is a system to provide multiple views on a display screen that mayseparately viewed by one or more viewers.

Under some embodiments, the device 800 comprises an interconnect orcrossbar 805 or other communication means for transmission of data. Thedata may include audio-visual data and related control data. The device800 may include a processing means such as one or more processors 810coupled with the interconnect 805 for processing information. Theprocessors 810 may comprise one or more physical processors and one ormore logical processors. Further, each of the processors 810 may includemultiple processor cores. The interconnect 805 is illustrated as asingle interconnect for simplicity, but may represent multiple differentinterconnects or buses and the component connections to suchinterconnects may vary. The interconnect 805 shown in FIG. 8 is anabstraction that represents any one or more separate physical buses,point-to-point connections, or both connected by appropriate bridges,adapters, or controllers. The interconnect 805 may include, for example,a system bus, a PCI or PCIe bus, a HyperTransport or industry standardarchitecture (ISA) bus, a small computer system interface (SCSI) bus, aIIC (I2C) bus, or an Institute of Electrical and Electronics Engineers(IEEE) standard 1394 bus, sometimes referred to as “Firewire”.(“Standard for a High Performance Serial Bus” 1394-1995, IEEE, publishedAug. 30, 1996, and supplements) The device 800 further may include aserial bus, such as USB bus, to which may be attached one or more USBcompatible connections.

In some embodiments, the device 800 further comprises a random accessmemory (RAM) or other dynamic storage device as a memory 815 for storinginformation and instructions to be executed by the processors 810.Memory 815 also may be used for storing data for data streams orsub-streams. RAM memory includes, for example, dynamic random accessmemory (DRAM), which requires refreshing of memory contents, and staticrandom access memory (SRAM), which does not require refreshing contents,but at increased cost. DRAM memory may include synchronous dynamicrandom access memory (SDRAM), which includes a clock signal to controlsignals, and extended data-out dynamic random access memory (EDO DRAM).In some embodiments, memory of the system may contain certain registersor other special purpose memory. The device 800 also may comprise a readonly memory (ROM) 830 or other static storage device for storing staticinformation and instructions for the processors 810. The device 800 mayinclude one or more non-volatile memory elements 835 for the storage ofcertain elements.

In some embodiments, a data storage 820 may be coupled to theinterconnect 805 of the device 800 for storing information andinstructions. The data storage 820 may include a magnetic disk, anoptical disc and its corresponding drive, or other memory device. Suchelements may be combined together or may be separate components, andutilize parts of other elements of the device 800. In some embodiments,the data storage may include storage of content data 828 forpresentation on a multi-view display.

The device 800 may also be coupled via the interconnect 805 to amulti-view display device or element 840. In some embodiments, thedisplay may include a liquid crystal display (LCD), a plasma display, orany other display technology, for displaying information or content toan end user. In some embodiments, the display 840 may be utilized todisplay multiple images, including different 2D and 3D images todifferent viewers. In this illustration, the display device or element840 is shown to be simultaneously presenting multiple images, such as afirst image 842, a second image 844, through an nth image 846. In someembodiments, the display device or element may include or operate inconjunction with one or more filters 850, the one or more filters 850operating to separate views 852 that are intended for one or moreviewers 855. The filters 850 may include filtering devices or elements165-175 illustrated in FIG. 1 and filtering elements such as glasses 305and lens or filter 355 illustrated in FIG. 3. In some environments, thedisplay 840 may include an audio device, such as a speaker for providingaudio information, including the audio portion of a program.

In some embodiments, an input device 860 may be coupled to orcommunicate with the apparatus or system 800 for communicatinginformation and/or command selections to the processors 810. In variousimplementations, the input device 860 may be a remote control, keyboard,a keypad, a touch screen, voice activated system, or other input device,or combinations of such devices. In some embodiments, the device orsystem may further include a cursor control device 865, such as a mouse,a trackball, touch pad, or other device for communicating directioninformation and command selections to the one or more processors 810 andfor controlling cursor movement on the display 840.

One or more transmitters or receivers 870 may also be coupled to theinterconnect 805. In some embodiments, the device 800 may include one ormore ports 875 for the reception or transmission of data. Data that maybe received or transmitted may include 3D or 2D content data 880. Thedevice 800 may further include one or more antennas 878 for thereception of data via radio signals. The device 800 may also comprise apower device or system 885, which may comprise a power supply, abattery, a solar cell, a fuel cell, or other system or device forproviding or generating power. The power provided by the power device orsystem 885 may be distributed as required to elements of the device 800.

In some embodiments, certain forms of video processing may be performedat various locations in a multi-view display system or device. In someembodiments, the system or device may perform filtering that isappropriate to the display or transport format. For example, the systemor device may vertically low-pass filter an image that will be displayedon a line-alternate display.

In some embodiments, a system or device may mix the audio related to avideo stream, rather than pass all channels from all the inputs. Forexample, in a two-player gaming application, the system or device maymix a first player's audio down to mono, and present the mixed audio asthe left audio channel, and a second player's audio to mono and presentthat as the right channel. In some embodiments, more complex processesfor audio, such as surround sound or virtual surround sound, may beimplemented.

In some embodiments, displays and source devices contain one or moreframe buffers that are used to overlay a user interface over video data.In some embodiments, each stream for a multi-view application mayutilize its own interface. In some embodiments, a device that presentsuser interfaces contains an overlay frame buffer for each stream.

With the display of video streams on a multi-view display, there may bea potential for the viewing by one user of a video stream intended foranother user (such as viewing without glasses, or in circumstances inwhich an unintended video stream is not sufficiently filtered and bleedsthrough the viewing of another video stream). In some embodiments, amulti-display device or system may add extra streams to an input streamin order to obscure the others on the display. In one example, given afirst stream of video data, a device or system may add a second streamthat is the inverse of the first stream. When viewed without glasses ona display, combination of the video streams will appear (approximately)to be grey.

In the description above, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present invention. It will be apparent, however, toone skilled in the art that the present invention may be practicedwithout some of these specific details. In other instances, well-knownstructures and devices are shown in block diagram form. There may beintermediate structure between illustrated components. The componentsdescribed or illustrated herein may have additional inputs or outputsthat are not illustrated or described. The illustrated elements orcomponents may also be arranged in different arrangements or orders,including the reordering of any fields or the modification of fieldsizes.

The present invention may include various processes. The processes ofthe present invention may be performed by hardware components or may beembodied in computer-readable instructions, which may be used to cause ageneral purpose or special purpose processor or logic circuitsprogrammed with the instructions to perform the processes.Alternatively, the processes may be performed by a combination ofhardware and software.

Portions of the present invention may be provided as a computer programproduct, which may include a computer-readable medium having storedthere on computer program instructions, which may be used to program acomputer (or other electronic devices) to perform a process according tothe present invention. The computer-readable medium may include, but isnot limited to, floppy diskettes, optical disks, CD-ROMs (compact diskread-only memory), and magneto-optical disks, ROMs (read-only memory),RAMs (random access memory), EPROMs (erasable programmable read-onlymemory), EEPROMs (electrically-erasable programmable read-only memory),magnet or optical cards, flash memory, or other type ofmedia/computer-readable medium suitable for storing electronicinstructions. Moreover, the present invention may also be downloaded asa computer program product, wherein the program may be transferred froma remote computer to a requesting computer.

Many of the methods are described in their most basic form, butprocesses may be added to or deleted from any of the methods andinformation may be added or subtracted from any of the describedmessages without departing from the basic scope of the presentinvention. It will be apparent to those skilled in the art that manyfurther modifications and adaptations may be made. The particularembodiments are not provided to limit the invention but to illustrateit.

If it is said that an element “A” is coupled to or with element “B,”element A may be directly coupled to element B or be indirectly coupledthrough, for example, element C. When the specification states that acomponent, feature, structure, process, or characteristic A “causes” acomponent, feature, structure, process, or characteristic B, it meansthat “A” is at least a partial cause of “B” but that there may also beat least one other component, feature, structure, process, orcharacteristic that assists in causing “B.” If the specificationindicates that a component, feature, structure, process, orcharacteristic “may”, “might”, or “could” be included, that particularcomponent, feature, structure, process, or characteristic is notrequired to be included. If the specification refers to “a” or “an”element, this does not mean there is only one of the described elements.

An embodiment is an implementation or example of the invention.Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments. The various appearances of “an embodiment,”“one embodiment,” or “some embodiments” are not necessarily allreferring to the same embodiments. It should be appreciated that in theforegoing description of exemplary embodiments of the invention, variousfeatures of the invention are sometimes grouped together in a singleembodiment, figure, or description thereof for the purpose ofstreamlining the disclosure and aiding in the understanding of one ormore of the various inventive aspects.

What is claimed is:
 1. An apparatus comprising: a display screen todisplay a plurality of views simultaneously; a controller circuitconfigured to control the plurality of views presented on the displayscreen; input terminals configured to receive a plurality of streams ofvideo data from one or more sources, wherein the input terminals areconfigured to receive the streams of video data; and an aligning deviceto cause the plurality of streams of video data to be in a commonformat, responsive to the streams of video data being of differentformats; wherein the apparatus is configurable by the controller circuitto provide a plurality of view settings, the view settings including afirst setting in which the apparatus provides a single view to eachviewer of the display screen and a second setting in which the apparatusprovides a first view to a first viewer of the display screen and asecond view to a second viewer of the display screen; wherein a firstfiltering element filters views presented to viewers of the displayscreen such that an intended view is displayed to one or more viewers;and wherein the controller circuit includes a switch that switchesbetween the first setting and the second setting based on control of aviewer, content in the streams of video data or metadata in the streamsof video data.
 2. The apparatus of claim 1, wherein the first view isgenerated from a first stream of video data and the second view isgenerated from a second stream of video data.
 3. The apparatus of claim1, wherein in the second setting the first filtering element filters theviews presented to the first viewer such that the first view isdisplayed to the first user and the second view is obscured from thefirst viewer and a second filtering element filters the views presentedto the second viewer such that the second view is displayed to thesecond viewer and the first view is obscured from the second viewer. 4.The apparatus of claim 1, wherein the first setting provides a samethree-dimensional (3D) view to each viewer, and the second settingprovides a first two-dimensional (2D) view to the first viewer and asecond 2D view to the second viewer.
 5. The apparatus of claim 1,wherein the apparatus further includes a transmitter to transmit signalsto the first filtering element.
 6. The apparatus of claim 5, wherein thesignals to the first filtering element instruct the first filteringelement to switch to the intended view.
 7. The apparatus of claim 1,wherein the apparatus further includes a receiver to receive signalsfrom the first filtering element.
 8. The apparatus of claim 7, whereinthe signals from the first filtering element provide a status of thefirst filtering element.
 9. The apparatus of claim 1, wherein theapparatus further includes a device to provide a head-tracking signal,wherein the device is further to detect a position of a particularviewer relative to the display screen.
 10. The apparatus of claim 9,wherein the head-tracking signal of the particular viewer is used toselectively deliver a single view to be a view point from the particularviewer's position.
 11. The apparatus of claim 9, wherein the headtracking signal is used to provide a motion parallax effect.
 12. Theapparatus of claim 1, wherein the aligning device causes the streams ofvideo data to be in the common format by choosing a primary input,observing a primary input format on the primary input, and advertisingthe primary input format to at least a subset of sources of the streamsof video data.
 13. The apparatus of claim 1, wherein the aligning devicecausing the streams of video data to be in the common format includesthe aligning device requiring one or more of a common resolution, acommon frame rate, or a common interlace status.
 14. A systemcomprising: a display screen for display of a plurality of images; inputterminals configured to receive a plurality of streams of video datafrom one or more sources, wherein the input terminals are configured toreceive the streams of video data; an aligning device to cause theplurality of streams of video data to be in a common format, responsiveto the streams of video data being of different formats; a signalelement to provide the plurality of images to the display screen; acontrol unit including a controller circuit configured to control thedisplay of the plurality of images, the control unit to include a firstsetting for providing a same image to all viewers of the display screenand a second setting for providing a first image to a first viewer and asecond image to a second viewer, the control unit comprising a switchthat switches between the first setting and the second setting based oncontrol of a viewer, content in the streams of video data or metadata inthe streams of video data; and one or more filter elements to filter theimages displayed on the display screen.
 15. The system of claim 14,wherein the first image is generated from a first stream of video dataand the second image is generated from a second stream of video data.16. The system of claim 14, wherein the one or more filter elementsinclude a set of glasses for a first user.
 17. The system of claim 16,wherein the set of glasses includes a sound element to deliver audio tothe first user.
 18. The system of claim 16, wherein the set of glassesincludes a switch to switch the set of glasses between settings for thefirst image and the second image.
 19. The system of claim 18, whereinthe switch is controllable by the first user.
 20. The system of claim18, wherein the switch is controllable by content in the streams ofvideo data.
 21. The system of claim 18, wherein the switch iscontrollable by metadata introduced in a video stream.
 22. The system ofclaim 16, wherein the set of glasses includes a receiver and the controlunit includes a transmitter, and wherein the switch may be set inresponse to a signal sent by the controller circuit via the transmitterand received by the glasses via the receiver.
 23. The system of claim16, wherein the set of glasses includes one or more sensors.
 24. Thesystem of claim 23, wherein the one or more sensors sense a state of theone or more filter elements.
 25. The system of claim 23, wherein the oneor more sensors sense a direction of the set of glasses.
 26. The systemof claim 23, wherein the one or more sensors sense a position of thefirst user relative to the display screen.
 27. The system of claim 16,wherein the set of glasses includes a transmitter to transmit dataregarding a state of the set of glasses and wherein the control unitincludes a receiver to receive the data regarding the state of the setof glasses.
 28. The system of claim 16, wherein the set of glassesincludes a receiver to receive audio data from the control unit andwherein the control unit includes a transmitter to transmit the audiodata to the set of glasses.
 29. The system of claim 14, wherein the oneor more filter elements include a filter for the display screen.
 30. Thesystem of claim 14, wherein the first image and the second image arepolarized images with different polarization, and wherein the one ormore filter elements include a polarized filter.
 31. The system of claim14, wherein the first image and the second image are presented atalternating intervals, and wherein the one or more filter elementsinclude a shutter to open during intervals for a first view and closeduring intervals for a second view.
 32. The system of claim 31, whereinthe first view and the second view utilize different colors, and whereinthe one or more filter elements include a color filter.
 33. The systemof claim 14, wherein the aligning device requiring the one or moresources to provide the streams of video data in the common format bychoosing a primary input, observing a primary input format on theprimary input, and advertising the primary input format to at least asubset of sources of the streams of video data.